Final answer:
To find the width of the border of the wishing well, we need to first determine the volume of the well. The well is in the shape of a cylinder, so we can use the formula for the volume of a cylinder: V = πr^2h, where V is the volume, r is the radius, and h is the height.
Step-by-step explanation:
The student likely made a mistake in converting units or setting up the equation for the volume of concrete for the border of the cylindrical wishing well. The correct method includes converting cubic yards to cubic feet for the volume of concrete, inches to feet for the height, and using the formula for the volume of a cylinder to find the border width.
To find the width of the border of the wishing well, we need to first determine the volume of the well. The well is in the shape of a cylinder, so we can use the formula for the volume of a cylinder: V = πr^2h, where V is the volume, r is the radius, and h is the height.
The radius of the well is half of the diameter, which is 5 feet, so r = 2.5 feet. Given that the volume of concrete ordered for the well is 2.75 cubic yards, we need to convert the volume to cubic feet by using the conversion factor 1 cubic yard = 27 cubic feet. So, the volume in cubic feet is 2.75 x 27 = 74.25 cubic feet.
Now, we can use the formula V = πr^2h to solve for the height of the well: 74.25 = π(2.5)^2h. Solving for h, we find h ≈ 3.761 feet.
The border of the wishing well will have the same width as the well itself, which is the diameter of the well. So the width of the border will be 5 feet.